Medication safety and dosing

Safe medication practice is a chain: right person, right drug and form, right dose by math, right site watch, and an honest response when something goes wrong. Learn the chain once; items become pattern matching.

Identity, labels, and the rights

The rights only work if identity is solid. Use two approved identifiers (name and date of birth) every time. Room number, bed label, and “I know this client” do not qualify.

• Check the label against the MAR three times: when you pull it, when you prepare it, and at the bedside.
• Never borrow another client’s medication to “save a trip.”
• If the client reports an allergy to the drug in front of you, stop and clarify. Do not give “just this once.”

High-alert drugs need a second brain

Independent double-checks are for drugs that kill when the dose or concentration is wrong: insulin, heparin, opioids, chemotherapy, and IV potassium. Two nurses separately verify the order, dose, and pump settings. Not every intramuscular antibiotic needs that ritual.

• PCA: client-only button, scheduled sedation and respiratory checks, naloxone available, two-nurse pump check. No proxy dosing by family.
• IV potassium: diluted, preferably premixed, pump-infused after renal clearance is acceptable. Never IV push. Never run concentrate by gravity from the bedside.
• Hold cues beat rote give-rules: digoxin with hypokalemia, beta-blocker with marked bradycardia, ACE inhibitor with angioedema.

Forms you must not alter

Crushing changes how the drug is absorbed. Enteric-coated and extended-release (XR, ER, SR, XL, Contin) tablets are not for crushing or chewing. If the client cannot swallow, get a different form ordered. Scored tablets may be split when the order allows; unscored tablets are not assumed split-safe. Check expiration dates on every pull - expired stock is a hold, not a “probably fine.”

Verbal or telephone orders get a read-back of drug, dose, route, and frequency before you hang up. Clarify unusual doses. Do not accept incomplete prescriptions that omit route or dose and then guess from habit.

Injection routes and reconstitution

Parenteral routes are not interchangeable. Intradermal is nearly flat to the skin (classic TB testing). Subcutaneous sits in fatty tissue at about 45–90 degrees depending on needle length and client size. Intramuscular targets muscle at 90 degrees - adult deltoid, vastus lateralis, and ventrogluteal are the usual sites; dorsogluteal is avoided on modern exams because of sciatic risk. Do not give more volume than the site can hold; split doses or choose another site when the calculated milliliters exceed policy limits (often about 3 mL for many adult IM sites).

• Z-track for irritating IM meds: displace skin, inject, withdraw, then release skin to seal the track.
• Reconstitute powders with the diluent and volume pharmacy/label name; roll to dissolve - do not shake foamy biologics against the label.
• Insulin syringes measure units; tuberculin syringes measure small mL volumes - do not swap them for convenience.

Safe dose verification

Before you give a weight-based order, prove it fits the published or ordered maximum. The exam loves the nurse who holds an oversized order instead of silently trimming it.

1. Convert pounds to kilograms: lb ÷ 2.2. Do this before any mg/kg math.
2. Daily max = mg/kg/day × weight in kg. Single-dose max = daily max ÷ doses per day (or use the stated mg/kg/dose).
3. Compare the ordered amount to that ceiling. At or under → may give. Over → hold and clarify after rechecking weight and transcription.
4. Unit conversions before volume math: 1 g = 1000 mg; 1 mg = 1000 mcg. Desired ÷ have × volume only after units match.

Pump and drip patterns

Facility protocols set exact titration limits and notify thresholds for drips. When a stem gives a protocol number, use that number. Do not invent a personal “usual” rate.

Body surface area (BSA)

Some chemo and selected pediatric orders are written per square meter, not per kilogram. The exam usually hands you a BSA already, or asks you to use Mosteller: square root of (height in cm × weight in kg ÷ 3600). Then ordered mg/m² × BSA = milligrams to give. Convert to volume only after that. A child can have a “normal” mg/kg look and still be over the BSA max if someone skipped the m² step. Hold and clarify when the calculated dose exceeds the labeled or protocol ceiling; do not quietly trim it.

• Confirm height and weight are current before you trust a BSA on the MAR.
• Keep units: cm and kg for Mosteller. Inches and pounds need conversion first.
• mg/m² is not interchangeable with mg/kg. Use the formula the stem names.

IV site: three pictures, three actions

IV site complications sort into infiltration, phlebitis, and vesicant extravasation. Name the picture first; the first action follows the tissue story, not a generic restart.

A site that is soft, painless, with free flow and blood return is working. Do not restart a good line for habit.

Other parenteral emergencies

• Air embolism (sudden dyspnea, chest pain, hypotension with a central line risk): clamp the catheter, place the client left side, head down, give oxygen, notify.
• TPN interruption: do not stop cold and do not speed the next bag to “catch up.” Bridge with dextrose (often 10%) at the current rate per protocol to avoid rebound hypoglycemia.
• Confirm nasogastric placement before first use with the facility gold standard (commonly radiographic confirmation) plus supportive checks such as acidic aspirate pH. Do not rely on a deferred x-ray alone when the stem says confirmation is required now.

When an error happens

Once a wrong drug, dose, or route has already reached the client, the priority flips from administration technique to harm control. Assess first because you cannot choose the right rescue if you have not looked at the person in front of you - airway, breathing, circulation, and the symptoms that match what was given.

1. Assess the client (airway, breathing, circulation, relevant vitals and symptoms).
2. Notify the provider and follow emergency orders.
3. Complete the incident report honestly.
4. Monitor and document. Never falsify the MAR or give a second dose to “fix” the first without an order.

Notify next so the provider can order antidotes, fluids, monitoring, or transfer. The incident report comes after the client is stabilized and the provider knows - it is for system learning and legal honesty, not a substitute for bedside care. Keep monitoring because some toxicities declare late (opioids and sedation, insulin and delayed hypoglycemia).

The distractor that looks responsible is documenting or filing the report before you assess, or quietly giving another dose to “balance” the first without an order. Covering the MAR or delaying notification protects nobody and can delay the only intervention that matters. Edge case: if the error is caught before the drug is given, do not give it - correct the process, then report the near miss per policy. The sequence above is for drug that already reached the client.

How to reason under time pressure

1. Is identity and allergy clearance clean?
2. Is this a high-alert drug that needs a second check?
3. Does the math clear the safe range after lb→kg?
4. Does the IV site picture match infiltration, phlebitis, or extravasation?
5. If something already went wrong: assess, notify, report - in that order.

Pediatric medication technique

Children are not small adults with the same landmarks and volumes. Weight-based math still rules dosing, but technique prevents the injury that a correct milligram can still cause. Prefer oral liquids with an oral syringe - not a household teaspoon. For IM injections in infants, the vastus lateralis is the usual site; deltoid waits until muscle mass exists. Volume limits are smaller than adult habits; split doses or choose another route when the calculated volume exceeds site capacity.

• Never call medication “candy” - that teaching creates overdose risk at home.
• Involve the school-age child in choices that are real (which arm, after which story) without offering a choice to refuse a needed drug.
• Double-check high-alert peds doses (insulin, opioids, digoxin, chemo) with a second nurse when policy requires.

The distractor that looks kind is mixing the whole dose into a bottle the infant may not finish, or using the deltoid on a skinny infant because that is where adults get shots. Deliver the full ordered dose you can account for, in the site that matches the age.